1. From the Departments of Physiology (M.C.P.-C., H.K., Y.O., K.S.H.-S., L.G.N.) and Medicine (K.S.H.-S., L.L.H.,), Hypertension and Renal Center of Excellence (H.K., L.L.H., L.G.N.), Tulane University Health Sciences Center; and the Department of Physiology (L.M.H.-B.), Louisiana State University Health Sciences Center, New Orleans.